High energy propellant with reduced pollution

Abstract

This invention relates to energetic compositions, which offer increased performance in conjunction with a total absence of hydrogen chloride in the combustion products. The formulation avoids the use of halogen based oxidizers to prevent the formation of halogen based byproducts. The formulations disclosed herein use ammonium dinitramide as a primary oxidizer, which is a more energetic molecule than ammonium perchlorate. The solid propellant formulations disclosed herein comprise about 5 to about 10 weight % of at least one energetic binder, about 20 to about 35 weight % of an energetic plasticizer; about 25 to about 45 weight % of ammonium dinitramide as a primary oxidizer; about 0 to about 20 weight % of particulate aluminum having a particle size of about 1 mum to about 60 mum; and about 0 to about 20 weight % of ultrafine aluminum having a particle size of less than 1 mum.

What is claimed is:  
     
       1. A solid propellant formulation comprising: 
       about 5 to about 10 weight % of at least one energetic binder;  
       about 20 to about 35 weight % of an energetic plasticizer;  
       about 25 to about 45 weight % of ammonium dinitramide as a primary oxidizer;  
       about 10 to about 20 weight % of a metal fuel, wherein said metal fuel comprises particulate aluminum having a particle size of about 1 μm to about 60 μm and ultrafine aluminum having a particle size of less than 1 μm.  
     
     
       2. The solid propellant formulation of  claim 1 , wherein said energetic plasticizer is selected from the group consisting of butanetriol trinitrate, triethylene glycol dinitrate, nitroglycerine, glycidyl azide polymer terminated with azide, bis-(2,2-dinitropropyl) acetal/formal and butyl nitratoethylnitramine. 
     
     
       3. The solid propellant formulation of  claim 1 , wherein said energetic plasticizer is butanetriol trinitrate. 
     
     
       4. The solid propellant formulation of  claim 1 , wherein said energetic binder is selected from the group consisting of glycidyl azide polymer, a copolymer of (bis-azidoethyl) oxetane with (3-nitratomethyl-3-methyl) oxetane, 3-azidomethyl-3-methyl oxetane, bis-(nitratomethyl) oxetane, polyglycidyl nitrate, polypropylene glycol, hydroxy-terminated polycaprolactones, hydroxy-terminated polyesters, hydroxy-terminated polyethers, hydroxy-terminated polycaprolactone ether and hydroxy-terminated polyalkylene oxide. 
     
     
       5. The solid propellant formulation of  claim 1 , wherein said energetic binder is a hydroxy-terminated polyalkylene oxide having a molecular weight of about 24,000 daltons. 
     
     
       6. The solid propellant formulation of  claim 1 , wherein said metal fuel comprises about 10 weight % of said particulate aluminum having a particle size of about 1 μm to about 60 μm; and 
       about 10 weight % of said ultrafine aluminum having a particle size of less than 1 μm.  
     
     
       7. The solid propellant formulation of  claim 1 , further comprising at least one member selected from a curative, a crosslinker, a stabilizer, a cure catalyst, a bum rate catalyst, a bum rate modifier, an opacifier and a bonding agent. 
     
     
       8. The solid propellant formulation of  claim 6 , wherein said crosslinker is selected from the group consisting of hexamethylene diisocyanate, isophorone diisocyanate, toluene diisocyanate and polymeric hexamethylene diisocyanate. 
     
     
       9. The solid propellant formulation of  claim 6 , wherein said bum rate catalyst is aluminum oxide. 
     
     
       10. The solid propellant formulation of  claim 6 , wherein said cure catalyst is selected from the group consisting of triphenyl bismuth, triphenyltin chloride, dibutyltin diacetate, and dibutyltin dilaurate. 
     
     
       11. The solid propellant formulation of  claim 6 , wherein said curative is selected from the group consisting of hexamethylene diisocyanate, isophorone diisocyanate, toluene diisocyanate and the polymeric hexmethylene diisocyanate.